This invention is directed to a composite plastic article having a high clarity indicator, which may be back-lighted, and to a method of molding such a composite knob in a two shot molding process.
The composite plastic article of this invention and the method of making the composite plastic article will provide the following new and unobvious features:
a knob having a high clarity indicator line located on one face of the knob and in which the high clarity of the indicator line is obtained in part by a sharp cutoff of the outer covering of the plastic surrounding and covering only the perimeter of an uncovered portion of the core in the shape of an indicator line;
a sharp cutoff of the outer covering of the composite article around the uncovered portion of the core which is in the shape of an indicator line obtained in part through the use of a blocking tool;
a composite plastic article having a high clarity indicator formed as part of a fin which projects outwardly of the core and in which the wall of the indicator is thinner than the wall of the core;
a composite plastic article in which the outer covering is anchored to the core around the opening in the outer covering highlighting the indicator by protuberances in the core;
a composite plastic article in which a relatively thin light transmitting window for a light pipe is positioned in the core;
a composite plastic article in which a thin, light transmitting indicator window in the core is supported by a light pipe which functions as an anvil during the injection molding of the outer covering of the composite article;
a composite plastic article having a permanently installed light pipe formed with a hook that may be engageable either radially inwardly or radially outwardly and may be formed to be flexible; and
a method of making a composite plastic article in which the injection of the outer covering is directed through the tooling in a manner that prevents the core from being moved away from the mold cavity tooling.
Other objects of the invention may be found in the following specification, claims and drawings.